1. Field of Invention
This invention relates generally to syringe guide devices, specifically to a device with a needle-shielding syringe guide that can be adapted for use with one of a variety of common arterial syringes and that allows quick release of a syringe blood receptacle.
2. History of Technology
In order to insert the needle of a syringe into a targeted artery, a medical technician will often struggle with instability of the artery during the procedure; the artery may tend to move away from an incoming needle. A second problem is that the artery may be hard to locate. A third common problem is that safety is jeopardized by an over-exposed needle. A fourth problem is that it is difficult to maintain a straight path of insertion. A fifth problem is that it is impossible to keep exposed fingers away from the puncture site. The present invention solves these problems.
The withdrawal of arterial blood from a patient is a common procedure in today's health care settings. Arterial blood gas, or “ABG” analysis serves to provide vital information concerning the respiratory status of the patient. Blood is drawn anaerobically from an artery such as the radial, brachial, femoral, or dorsalis pedis artery, via a percutaneous needle puncture. The preferred site is the radial artery. A blood specimen is collected for direct measurement of the partial pressures of carbon dioxide (PaCO2) and oxygen (PaO2), hydrogen ion activity (pH), total hemoglobin (Hbtotal), oxyhemoglobin saturation (HbO2), and the dyshemoglobins carboxyhemoglobin (COHb) and methemoglobin (MetHb). Sampling typically may only be performed by trained and certified health care personnel.
A modified Allen Test (collateral circulation test) should always be performed by a technician before the technician inserts a needle into a patient's radial artery. The Allen Test determines if blood is capable of flowing through the ulnar artery. The ulnar artery is the only other source of blood to the hand aside from the radial artery. A negative test result is indicative of inadequate collateral blood supply to the hand and requires the selection of another location as the site for arterial access.
To obtain an arterial blood sample, the technician will first determine the precise location in which to insert the needle of a syringe into the artery of the patient. Once an appropriate site is located, the needle is inserted by the technician into the selected artery until the artery is penetrated and the syringe's blood receptacle fills with sufficient blood. Then, the needle is removed from within the artery, the wound is dressed, and the needle is capped to prevent needle injuries. The arterial blood draw process is difficult and prone to errors, even when the technician has ample experience. Because of the traumatic nature of the procedure, and the large number of complications that may arise, it is important for the technician to try to obtain the arterial blood properly and effectively on the first attempt. Prior art has seriously failed to provide technicians with adequate means to obtain a successful arterial blood sample regularly on the first attempt.
An unrestrained artery may tend to move away from an incoming needle, particularly in older patients whose skin has lost elasticity. A loss of elasticity in the skin creates a loss of stability around the artery, which allows the artery to roll around under the surface of the skin. It is possible for a needle tip to push the artery away from its path, causing the technician to miss the targeted artery completely. The present invention solves this problem by providing an artery stabilizer to hold the artery in place.
Currently, the technician will press her or his finger over the anticipated arterial puncture site and then estimate where the artery lies under that finger; it is a rough estimate and the technician often miscalculates. Alternatively, the technician may place two fingers over the artery and attempt to hold the artery between the fingertips, inserting the needle between the two fingertips to penetrate the artery. This method has its limitations; the technician should have a tight pair of gloves, cannot have long finger nails, and will rely on bulky fingertips to pinpoint a relatively thin artery between them, and this technique is impossible to use on infants and small children. The present invention uses an artery stabilizer to hold the artery within two integrated stabilizer fingers at the base of the device, and it partially occludes the artery during use; this creates an augmented pulse at the site where the needle will enter the artery, simplifying palpation of the artery and vastly diminishing the labor involved in identifying where to insert the needle. The artery stabilizer further allows the technician to keep any of the technician's exposed extremities substantially away from the puncture site while inserting the needle into the targeted artery, thus improving safety.
Because of low blood pressure, a patient's pulse may be weak and hard to locate. It is sometimes necessary for the technician to perform an arterial puncture “blindly,” merely stabbing the site where the technician considers the best option for obtaining arterial access. The present invention helps to create an augmented pulse that is palpable even in cases of low blood pressure.
Most ABG protocols allow a technician to try three consecutive needle insertions without removing the needle tip beyond the subcutaneous tissue. As the angle of insertion changes within the dermis, the needle slices through the tissue in its path, and may even lacerate the artery. Any change in the angle of needle insertion can inflict severe pain onto a conscious patient. Because of the structural design of the present invention, a straight, unswerving path of needle insertion into the artery is achieved. Currently, the often unsteady hand of the technician is used to guide the syringe needle down into the artery. A nervous hand can become quite jittery, and even a calm hand does not guarantee a straight path of insertion into and out of the vessel. The present invention provides a considerable improvement in this regard; pressing the artery stabilizer, at the base of the invention, down near the puncture site provides stability to the hand of the technician. The straight slot within the housing, which supports the syringe, vastly improves the likelihood of a direct and controlled line of insertion and extraction of the needle during a blood draw procedure, minimizing pain and trauma within the patient's dermal tissues and artery.
Often, the unrestrained nature of the current methods for inserting a needle into an artery causes the needle to become accidentally extracted from within the artery during a blood draw attempt, causing a cessation of blood flow. The present invention prevents this common mishap, by providing a solid, steady housing within which the syringe is securely held in place during the procedure.
According to standard ABG protocols, a needle should enter an artery at a steady angle of approximately 45 degrees in relation to the artery distal the heart near the insertion site; prior art relies on the technician to maintain that angle without any support. A proper angle of needle insertion is assured using the present invention, as a result of the base of the stabilizer fingers being properly angled in relation to the housing slot within which the syringe is maneuvered.